Modulation of Cytokines in Cancer Patients by Intravenous Ascorbate Therapy

The effect of intravenous vitamin C on clinical outcomes in patients with sepsis or septic shock: A meta-analysis of randomized controlled trials

Objectives

Vitamin C deficiency is common among patients with sepsis and has been associated with poor clinical outcomes. Nevertheless, the effect of intravenous (IV) vitamin C for the treatment of sepsis remains controversial. The purpose of this meta-analysis was to evaluate the effect of IV vitamin C in patients with sepsis or septic shock.

Methods

Electronic databases (PubMed, Embase, Scopus, and Cochrane Library) were searched from inception through May 25, 2022 for randomized controlled trials evaluating the effect of IV vitamin C treatment in patients with sepsis. The primary outcome was short-term mortality, and secondary outcomes including the duration of vasopressor, length of intensive care unit (ICU) stay, and Sequential Organ Failure Assessment (SOFA) score after vitamin C treatment. Subgroup analyses were performed based on the type of disease, dose and duration of IV vitamin C.

Results

A total of 10 studies were included, with a total sample of 755 septic patients. The IV vitamin C was associated with a significant reduction in the short-term mortality (OR 0.51, 95% CI 0.37–0.69, I² = 0%) and duration of vasopressor (MD −27.88, 95% CI −49.84 to −5.92, I² = 95%). The length of ICU stay (MD −0.68, 95% CI −2.13 to 0.78, I² = 74%) and SOFA score (MD −0.05, 95% CI −1.69 to 1.58, I² = 86%) were not significantly different between two groups.

Conclusion

In patients with sepsis or septic shock, the IV vitamin C reduced the short-term mortality rate and duration of vasopressor, with no effect on the length of ICU stay and SOFA score. Further trials are required to explore the optimal dosage and duration of IV vitamin C.

Systematic Review Registration

https://inplasy.com/inplasy-2022-6-0013/, identifier INPLASY202260013.

The Effects of Vitamin C on the Multiple Pathophysiological Stages of COVID-19

Currently available anti-viral drugs may be useful in reducing the viral load but are not providing the necessary physiological effects to reduce the SARS-CoV-2 complications efficiently. Treatments that provide better clinical outcomes are urgently needed. Vitamin C (ascorbic acid, AA) is an essential nutrient with many biological roles that have been proven to play an important part in immune function; it serves as an antioxidant, an anti-viral, and exerts anti-thrombotic effects among many other physiological benefits. Research has proven that AA at pharmacological doses can be beneficial to patients with acute respiratory distress syndrome (ARDS) and other respiratory illnesses, including sepsis. In addition, High-Dose Intravenous Vitamin C (HDIVC) has proven to be effective in patients with different viral diseases, such as influenza, chikungunya, Zika, and dengue. Moreover, HDIVC has been demonstrated to be very safe. Regarding COVID-19, vitamin C can suppress the cytokine storm, reduce thrombotic complications, and diminish alveolar and vascular damage, among other benefits. Due to these reasons, the use of HDIVC should be seriously considered in complicated COVID-19 patients. In this article, we will emphasize vitamin C’s multiple roles in the most prominent pathophysiological processes presented by the COVID-19 disease.

Embracing cancer immunotherapy with vital micronutrients

Immunotherapy is now commonly prescribed to cancer patients, but autoimmune-related adverse events are considerable. For severe, life-threatening side effects, cessation of therapy seems unavoidable, let alone intensive medical care required for patching up the adverse events. Even without serious adverse events, the response rates are too low and various combinatory regimens have been tried. However, toxicities are also added on, unless the adjuvant agents have remarkably few side effects. Actually, micronutrients are usually taken by a majority of cancer patients as nutritional support or to boost the immune function, let alone hoping to counteract treatment side effects. Recent studies have shown that combinations of micronutrients exert pleiotropic effects in controlling tumor growth and metastasis by modulating the tumor microenvironment, enhancing gut microbiota immune functions, and providing adjunct nutritional support to micronutrient deficient cancer patients. A higher than recommended dietary allowance micronutrient dose is proposed to reduce the toxic free radicals generated as a result of immunotherapy and tumor metabolism. This is not only helpful for managing treatment side effects but also enhancing treatment efficacy. As micronutrient supplementation is also useful to improve patients’ quality of life, prolong survival, and sustain compliance to immunotherapy, further investigations are mandatory.

Combinatorial Therapy of High Dose Vitamin C and PARP Inhibitors in DNA Repair Deficiency: A Series of 8 Patients

Background:

Tumor-specific DNA repair defects are ubiquitous in cancerous tissue, which offers a potential for clinical gain to build on these perturbations. Intravenous high-dose vitamin C (IVC) triggers the formation of hydrogen peroxide (H₂O₂), which contributes to Fenton chemistry producing hydroxyl radicals (-OH), causing selective damage to DNA. Herein, we evaluated the therapeutic response to IVC and PARP inhibitors (PARPi) in combination in 8 patients with a deficiency of homologous recombination repair system (dHRR) in a 3-year period.

Material and Methods:

Eight patients with progressive stage IV malignancy, who were pre-treated with conventional methods, were admitted to our clinic. Subsequent therapy has included IVC at a dose that was set to be in the range of 1 to 1.5 g/kg, although 1.25 g/kg was dominantly administered. Furthermore, following genomic evaluation, PARPi (niraparib or olaparib or talazoparib) was chosen to be used in combination with IVC which was administered 2 to 4 times a week.

Results:

In the present study, we achieved partial response in 5 patients and complete response in 3 patients. Grade 2 anemia and fatigue toxicities were observed in some cases, while grade 3 toxicity was not found in any of the patients.

Conclusion:

Our 8 patient case study shows that IVC could be a plausible additional therapy for HRR deficiency. Although the single agent PARPi therapy is effective for metastatic disease, an overall survival (OS) advantage has not been demonstrated. Our results suggest that adding IVC can improve PARPi therapy outcomes. To fully endorse the results stated above, combinatorial therapy of intravenous high dose vitamin C and PARP inhibitors needs to be reviewed in broader cohorts of patients.

Common anti-oxidant vitamin C as an anti-infective agent with remedial role on SARS-CoV-2 infection. An update

Coronavirus disease -2019 (COVID-19) has led to a worldwide multifaceted crisis. The medical world agonizes to contend with the problem, but a string of tested medications has been proven unavailing. Vitamin C is well described as a salutary antioxidant and some trials conclude that it may be a potential antiviral drug. In high doses, Vitamin C can alternate crucial steps in the pathogenesis of sepsis and acute respiratory distress syndrome. This dynamic was the driving force behind trials around the world that tried immunonutrition as a weapon against clinical entities. We summarize the mechanisms of action of Vitamin C and its role against infections and the current literature referring to the potential role of Vitamin C in SARS-CoV-2 infection, also as a contingent treatment agent.

High-Dose Vitamin C in Advanced-Stage Cancer Patients

High-dose intravenously administered vitamin C (IVC) is widely used in cancer patients by complementary and alternative medicine practitioners. The most frequent indications for IVC therapy result from the belief in its effectiveness as a potent anti-cancer agent which additionally enhances chemosensitivity of cancer cells and reduces chemotherapy-related toxicities and fatigue intensity. In this narrative review, we decided to deal with this issue, trying to answer the question whether there is any scientific evidence supporting the rationale for application of high-dose IVC therapy in advanced-stage cancer patients. Although results obtained from preclinical studies demonstrated that millimolar ascorbate plasma concentrations achievable only after IVC administration were cytotoxic to fast-growing malignant cells and inhibited tumor growth as well as prolonged the survival of laboratory animals, such positive effects were not found in human studies with advanced-stage cancer patients. We also have not found the rationale for the use of IVC to increase the effectiveness of chemotherapy and to reduce the chemotherapy-induced toxicity in the above mentioned group. Nevertheless, in palliative care, high-dose IVC might be considered as a therapy improving the quality of life and reducing cancer-related symptoms, such as fatigue and bone pain. However, because of the absence of placebo-controlled randomized trials on IVC efficacy in advanced-stage cancer patients, the placebo effect cannot be excluded.

Ascorbate-induced oxidative stress mediates TRP channel activation and cytotoxicity in human etoposide-sensitive and -resistant retinoblastoma cells

There are indications that pharmacological doses of ascorbate (Asc) used as an adjuvant improve the chemotherapeutic management of cancer. This favorable outcome stems from its cytotoxic effects due to prooxidative mechanisms. Since regulation of intracellular Ca2+ levels contributes to the maintenance of cell viability, we hypothesized that one of the effects of Asc includes disrupting regulation of intracellular Ca2+ homeostasis. Accordingly, we determined if Asc induced intracellular Ca2+ influx through activation of pertussis sensitive Gi/o-coupled GPCR which in turn activated transient receptor potential (TRP) channels in both etoposide-resistant and -sensitive retinoblastoma (WERI-Rb1) tumor cells. Ca2+ imaging, whole-cell patch-clamping, and quantitative real-time PCR (qRT-PCR) were performed in parallel with measurements of RB cell survival using Trypan Blue cell dye exclusion. TRPM7 gene expression levels were similar in both cell lines whereas TRPV1, TRPM2, TRPA1, TRPC5, TRPV4, and TRPM8 gene expression levels were downregulated in the etoposide-resistant WERI-Rb1 cells. In the presence of extracellular Ca2+, 1 mM Asc induced larger intracellular Ca2+ transients in the etoposide-resistant WERI-Rb1 than in their etoposide-sensitive counterpart. With either 100 µM CPZ, 500 µM La3+, 10 mM NAC, or 100 µM 2-APB, these Ca2+ transients were markedly diminished. These inhibitors also had corresponding inhibitory effects on Asc-induced rises in whole-cell currents. Pertussis toxin (PTX) preincubation blocked rises in Ca2+ influx. Microscopic analyses showed that after 4 days of exposure to 1 mM Asc cell viability fell by nearly 100% in both RB cell lines. Taken together, one of the effects underlying oxidative mediated Asc-induced WERI-Rb1 cytotoxicity stems from its promotion of Gi/o coupled GPCR mediated increases in intracellular Ca2+ influx through TRP channels. Therefore, designing drugs targeting TRP channel modulation may be a viable approach to increase the efficacy of chemotherapeutic treatment of RB. Furthermore, Asc may be indicated as a possible supportive agent in anti-cancer therapies.

Mechanisms and Applications of the Anti-cancer Effect of Pharmacological Ascorbic Acid in Cervical Cancer Cells

In recent years, L-ascorbic acid (L-AA), or vitamin C, has been attracting attention as a potential anticancer drug that mediates hydrogen peroxide-induced oxidation and ten-eleven translocation 2-catalyzed DNA demethylation. However, the precise mechanism by which L-AA acts remains unclear. We examined the cytotoxic effects of L-AA or sodium ascorbate in human cervical carcinoma cells by assessing cell viability, expression of cell cycle-related mRNAs and proteins, and mitochondrial functions, and by performing flow cytometric analyses of cell cycle profiles, apoptosis, cell proliferation, and production of reactive oxygen species (ROS). We later tested the effects of ascorbates in combination with two first-line chemotherapeutic drugs, cisplatin, and doxorubicin. At pharmacological concentrations (1–10 mM), L-AA increased ROS levels; decreased levels of several cell cycle-related proteins, including p53, p21, cyclin D1, and phosphorylated histone 3 at serine residue 10; induced DNA damage, as indicated by changes in γH2A.x; decreased levels of the anti-oxidative transcription factor Nrf2; and increased levels of catalase, superoxide dismutase 1, and endoplasmic reticulum stress-related indicators, such as the p-eIF2α/eIF2α ratio and CHOP levels. L-AA also promoted cell proliferation and induced apoptosis and mitochondrial dysfunction. Finally, L-AA increased the susceptibility of HeLa cells to cisplatin and doxorubicin. These findings provide insight into how the adjustment of the cellular ROS status through L-ascorbate (L-AA or sodium ascorbate) administration could potentially synergistically enhance the efficacy of cancer therapies.

On the physiological and cellular homeostasis of ascorbate

Recent interest in the role of ascorbate in crucial metabolic processes is driven by the growing number of medical reports that show beneficial effects of ascorbate supplementation for maintaining general well-being and recovery from a variety of medical conditions. The effect of ascorbate on the local body environment highly depends on its local concentration; at low concentrations it can cause the reduction of reactive oxygen and facilitate activities of enzymes, while at high concentrations it generates free radicals by reducing ferric ions. Ascorbate serving as an electron donor assists the iron-containing proteins and the iron transfer between various aqueous compartments. These functions require effective and adjustable mechanisms responsible for ascorbate biodistribution. In the paper we propose a new biophysical model of ascorbate redistribution between various aqueous body compartments. It combines recent experimental evidence regarding the ability of ascorbate to cross the lipid bilayer by unassisted diffusion, with active transport by well-characterized sodium vitamin C transporter (SVCT) membrane proteins. In the model, the intracellular concentration of ascorbate is maintained by the balance of two opposing fluxes: fast active and slow passive transport. The model provides a mechanistic understanding of ascorbate flux across the epidermal barrier in the gut as well as the role of astrocytes in ascorbate recycling in the brain. In addition, ascorbate passive diffusion across biological membranes, which depends on membrane electric potentials and pH gradients, provides the rationale for the correlation between ascorbate distribution and the transfer of iron ions inside a cell. The proposed approach provides, for the first time, a mechanistic account of processes leading to ascorbate physiological and cellular distribution, which helps to explain numerous experimental and clinical observations.

The Emerging Role of Vitamin C as a Treatment for Sepsis

Sepsis, a life-threatening organ dysfunction due to a dysregulated host response to infection, is a leading cause of morbidity and mortality worldwide. Decades of research have failed to identify any specific therapeutic targets outside of antibiotics, infectious source elimination, and supportive care. More recently, vitamin C has emerged as a potential therapeutic agent to treat sepsis. Vitamin C has been shown to be deficient in septic patients and the administration of high dose intravenous as opposed to oral vitamin C leads to markedly improved and elevated serum levels. Its physiologic role in sepsis includes attenuating oxidative stress and inflammation, improving vasopressor synthesis, enhancing immune cell function, improving endovascular function, and epigenetic immunologic modifications. Multiple clinical trials have demonstrated the safety of vitamin C and two recent studies have shown promising data on mortality improvement. Currently, larger randomized controlled studies are underway to validate these findings. With further study, vitamin C may become standard of care for the treatment of sepsis, but given its safety profile, current treatment can be justified with compassionate use.

Intravenous Vitamin C for Cancer Therapy - Identifying the Current Gaps in Our Knowledge

The use of intravenous vitamin C (IVC) for cancer therapy has long been an area of intense controversy. Despite this, high dose IVC has been administered for decades by complementary health care practitioners and physicians, with little evidence base resulting in inconsistent clinical practice. In this review we pose a series of questions of relevance to both researchers and clinicians, and also patients themselves, in order to identify current gaps in our knowledge. These questions include: Do oncology patients have compromised vitamin C status? Is intravenous the optimal route of vitamin C administration? Is IVC safe? Does IVC interfere with chemotherapy or radiotherapy? Does IVC decrease the toxic side effects of chemotherapy and improve quality of life? What are the relevant mechanisms of action of IVC? What are the optimal doses, frequency, and duration of IVC therapy? Researchers have made massive strides over the last 20 years and have addressed many of these important aspects, such as the best route for administration, safety, interactions with chemotherapy, quality of life, and potential mechanisms of action. However, we still do not know the answers to a number of fundamental questions around best clinical practice, such as how much, how often and for how long to administer IVC to oncology patients. These questions point the way forward for both basic research and future clinical trials.

Vitamin C and Immune Function

Vitamin C is an essential micronutrient for humans, with pleiotropic functions related to its ability to donate electrons. It is a potent antioxidant and a cofactor for a family of biosynthetic and gene regulatory enzymes. Vitamin C contributes to immune defense by supporting various cellular functions of both the innate and adaptive immune system. Vitamin C supports epithelial barrier function against pathogens and promotes the oxidant scavenging activity of the skin, thereby potentially protecting against environmental oxidative stress. Vitamin C accumulates in phagocytic cells, such as neutrophils, and can enhance chemotaxis, phagocytosis, generation of reactive oxygen species, and ultimately microbial killing. It is also needed for apoptosis and clearance of the spent neutrophils from sites of infection by macrophages, thereby decreasing necrosis/NETosis and potential tissue damage. The role of vitamin C in lymphocytes is less clear, but it has been shown to enhance differentiation and proliferation of B- and T-cells, likely due to its gene regulating effects. Vitamin C deficiency results in impaired immunity and higher susceptibility to infections. In turn, infections significantly impact on vitamin C levels due to enhanced inflammation and metabolic requirements. Furthermore, supplementation with vitamin C appears to be able to both prevent and treat respiratory and systemic infections. Prophylactic prevention of infection requires dietary vitamin C intakes that provide at least adequate, if not saturating plasma levels (i.e., 100–200 mg/day), which optimize cell and tissue levels. In contrast, treatment of established infections requires significantly higher (gram) doses of the vitamin to compensate for the increased inflammatory response and metabolic demand.

High-Dose Intravenous Vitamin C Treatment of a Child with Neurofibromatosis Type 1 and Optic Pathway Glioma: A Case Report

Patient: Male, 1

Final Diagnosis: Optic glioma

Symptoms: Visual problems

Medication: —

Clinical Procedure: Intravenous vitamin C

Specialty: Oncology

Vitamin C, a Multi-Tasking Molecule, Finds a Molecular Target in Killing Cancer Cells

Early work in the 1970s by Linus Pauling, a twice-honored Nobel laureate, led to his proposal of using high-dose vitamin C to treat cancer patients. Over the past several decades, a number of studies in animal models as well as several small-scale clinical studies have provided substantial support of Linus Pauling's early proposal. Production of reactive oxygen species (ROS) via oxidation of vitamin C appears to be a major underlying event, leading to the selective killing of cancer cells. However, it remains unclear how vitamin C selectively kills cancer cells while sparing normal cells and what the molecular targets of high-dose vitamin C are. In a recent article published in Science (2015 December 11; 350(6266):1391-6. doi: 10.1126/science.aaa5004), Yun et al. reported that vitamin C selectively kills KRAS and BRAF mutant colorectal cancer cells by targeting glyceraldehyde 3-phosphate dehydrogenase (GAPDH) through an ROS-dependent mechanism. This work by Yun et al. along with other findings advances our current understanding of the molecular basis of high-dose vitamin C-mediated cancer cell killing, which will likely give an impetus to the continued research efforts aiming to further decipher the novel biochemistry of vitamin C and its unique role in cancer therapy.